Unfortunately it probably isn't the best thing to do if you're not expecting people to pay you in the near future. I am an AdWords pro and used it to promote my channel (I'll go into economics shortly) but I had services and courses to sell so people may have paid me in the future.
If you want to run a test for a comedy channel, first you need to define what success is. Is it X amount of views? X amount of subs? Once you are comfortable with that, then next you need to target your ads carefully.
For a comedy channel I would target other comedy channels that you think fans would like your comedy too and see if that works. For my experiment, I wanted subs and targeted large affinity audiences and ended up with a cost per sub of £0.50 which isn't too bad, but it's NO WAY to grow a channel. It was early days and I wanted to at least have somebody watching.
Hope that helps!